Since 1981, a centralized histology laboratory has provided histologic services to investigators at The University of Texas M. D. Anderson Cancer Center. The aim of the Research Histopathology Facility (RHF) is to provide technical support and consultation, develop and apply appropriate techniques, and maintain the consistency and high quality needed to perform these techniques. The RHF processes fixed and frozen specimens for routine histologic analysis, immunohistochemistry, in situ hybridization, and special staining of tissue sections. The RHF is available to all faculty at the M. D. Anderson with preference given to investigators with peer-reviewed grants. The RHF occupies 375 sq ft of recently renovated laboratory space in the Department of Pathology and 370 sq ft in the R.E. "Bob" Smith Research Building on the South Campus. Among the services provided are rapid preparation of high-quality standard histologic sections; application of special technologies as needed for selected projects, including preparation of frozen sections and tissue sections for histochemical, immunohistochemical, and in situ hybridization analysis; consultation with investigators to tailor technologies and methodologies to their special needs; and referral for consultation by organ-site subspecialty pathologists on interpretation of histopathology. The RHF utilizes state-of-the-art equipment to complete this work. During the past 2 years, both laboratories have upgraded their equipment to better serve their users. Purchases include the following: Shandon Pathcentre and Gemini Automatic Stainer, Tissue Tek Embedding Unit, Leica CM1850 Cryostat, Leica RM2155 fully Automatic Rotary Microtome and Shurmark Slide Labeler. The RHF currently maintains a staff that includes a Shared Resource Director, a Resource Co-Director, a Resource Chief Technician, a Resource Senior Histology Technician, and a Resource Lab Tech Assistant II. During the past 5 years, the RHF was used by 98 investigators, 68 of whom had peer-reviewed funding. The 68 users with peer-reviewed funding accounted for 95% of utilization. The users represented 18 different programs. Use of this resource has increased by 20% since 1998. Future plans include increasing the efficiency of the RHF by refining the data-handling process.